Kawasaki Heavy Industries completed construction of the world's first liquid-hydrogen (LH2) carrier, the Suiso Frontier, albeit without any storage tanks, in Japan in December 2019, as part of the $359m Hydrogen Energy Supply Chain (HESC) pilot project.

Its 1,250-cubic-metre vacuum-insulated LH2 storage tank was installed in March 2020, but it took until July 2021 for the storage equipment to be given approval-in-principle by Japanese classification society ClassNK, partly due to the fact that foreign engineers were unable to travel to Japan due to the Covid pandemic.

The vessel finally set sail from Australia to Japan with the world's first international shipment of LH2 (made from unabated brown coal) in January 2022. It emerged months later that one-metre flames were seen on deck when it was still stationed at the Australian port of Hastings — prompting an investigation by the Australian Transport Safety Bureau into the 'serious incident'.

The government agency finally concluded in February 2023 that an incorrectly fitted valve and an ineffective automated safety system caused the flames, which occured when the ship's gas combustion engine was switched on to burn LH2 boil-off gas (ie, the small proportion of the stored hydrogen that gasifies when it reaches boiling point [minus-253°C] due to warmer temperatures outside the tank).

Nevertheless, the trial was deemed a success and in March last year, the Japanese government earmarked ¥220bn ($1.6bn) to the HESC consortium for a follow-up commercial-demonstration project to ship 30,000 tonnes a year of hydrogen (made from brown coal with carbon capture) from the Port of Hastings to Japan.

In May 2022, Kawasaki announced that the design for a new long-distance LH2 carrier with 160,000 cubic metres of LH2 storage capacity had been given technical approval by ClassNK. But the Japanese shipbuilder continued to work on an LH2 cargo containment system, with technical development only being completed in June 2023, with no further information forthcoming since then.

And in April 2023, French oil major TotalEnergies announced that it was designing an LH2 carrier with 150,000 cubic metres of storage in conjunction with naval architect LMG Marin, gas technology provider GTT and classification society Bureau Veritas (BV).

That design was given approval-in-principle by BV in February this year.

So to date, the only LH2 carrier built to date is the Suiso Frontier, but it was never intended to be a commercially viable vessel.

Why liquid hydrogen is still being pursued as a long-distance H2 carrier, despite its limitations and high costs